[alsa-devel] Applied "ASoC: topology: Check return value for snd_soc_add_dai_link()" to the asoc tree

[Mark Brown]

The patch

   ASoC: topology: Check return value for snd_soc_add_dai_link()

has been applied to the asoc tree at

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git for-5.5

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.  

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark

>From 76d2703649321c296df7ec0dafd50add96215de4 Mon Sep 17 00:00:00 2001
From: Dragos Tarcatu <dragos_tarcatu at mentor.com>
Date: Mon, 9 Dec 2019 18:39:38 -0600
Subject: [PATCH] ASoC: topology: Check return value for snd_soc_add_dai_link()

snd_soc_add_dai_link() might fail. This situation occurs for
instance in a very specific use case where a PCM device and a
Back End DAI link are given identical names in the topology.
When this happens, soc_new_pcm_runtime() fails and then
snd_soc_add_dai_link() returns -ENOMEM when called from
soc_tplg_fe_link_create(). Because of that, the link will not
get added into the card list, so any attempt to remove it later
ends up in a panic.

Fix that by checking the return status and free the memory in case
of an error.

Reviewed-by: Ranjani Sridharan <ranjani.sridharan at linux.intel.com>
Signed-off-by: Dragos Tarcatu <dragos_tarcatu at mentor.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart at linux.intel.com>
Link: https://lore.kernel.org/r/20191210003939.15752-2-pierre-louis.bossart@linux.intel.com
Signed-off-by: Mark Brown <broonie at kernel.org>
---
 sound/soc/soc-topology.c | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/sound/soc/soc-topology.c b/sound/soc/soc-topology.c
index 81d2af000a5c..65c2796b6e02 100644
--- a/sound/soc/soc-topology.c
+++ b/sound/soc/soc-topology.c
@@ -1933,11 +1933,13 @@ static int soc_tplg_fe_link_create(struct soc_tplg *tplg,
 	ret = soc_tplg_dai_link_load(tplg, link, NULL);
 	if (ret < 0) {
 		dev_err(tplg->comp->dev, "ASoC: FE link loading failed\n");
-		kfree(link->name);
-		kfree(link->stream_name);
-		kfree(link->cpus->dai_name);
-		kfree(link);
-		return ret;
+		goto err;
+	}
+
+	ret = snd_soc_add_dai_link(tplg->comp->card, link);
+	if (ret < 0) {
+		dev_err(tplg->comp->dev, "ASoC: adding FE link failed\n");
+		goto err;
 	}
 
 	link->dobj.index = tplg->index;
@@ -1945,8 +1947,13 @@ static int soc_tplg_fe_link_create(struct soc_tplg *tplg,
 	link->dobj.type = SND_SOC_DOBJ_DAI_LINK;
 	list_add(&link->dobj.list, &tplg->comp->dobj_list);
 
-	snd_soc_add_dai_link(tplg->comp->card, link);
 	return 0;
+err:
+	kfree(link->name);
+	kfree(link->stream_name);
+	kfree(link->cpus->dai_name);
+	kfree(link);
+	return ret;
 }
 
 /* create a FE DAI and DAI link from the PCM object */
-- 
2.20.1